Simple circuits can create complex behaviors

(aatishb.com)

247 points | by aatish 4 days ago

17 comments

  • Animats 15 hours ago

    The ancestor is not Braitenberg. It's Grey Walter's turtles.

    In 1948, W. Grey Walter built two simple robots that could sense light and touch.[1] Much complex behavior emerged. That's where this idea started.

    Watch the video.[2] It's very impressive for 1948 and tube technology. If you've seen an original Roomba, you've seen a similar level of intelligence. Rod Brooks went down this road. But it didn't go very far. There are severe limits to purely reactive robotics. It doesn't work well for anything that moves fast enough that inertia matters.

    [1] https://en.wikipedia.org/wiki/Elmer_and_Elsie_(robots)

    [2] https://www.youtube.com/watch?v=lLULRlmXkKo

    • robotresearcher 15 hours ago

      It’s very odd that Braitenberg didn’t cite Walter’s precedent in ‘Vehicles’. He very likely knew about Walter, Ashby’s homeostat, etc, and used the cybernetics terminology in some of his work.

      Fun historical note: the linked newsreel film was known about but unseen for a long time, then found by Owen Holland in the BBC Bristol archive around 1999. Either Owen or I sent it to Rod, to great enjoyment.

      Film includes operator-moves-trashcan-with-foot, a staple of mobile robot clips ever since.

      • dekhn 14 hours ago

        See also: https://cyberneticzoo.com/cyberneticanimals/1969-the-logo-tu... In my gifted & talented class in the 80's we were introduced to computers and I remember seeing the picture of "Irving" and thinking "Wow, I should learn LOGO to program robots when I grow up" (unfortunately, recursion scared me so I switched to BASIC and later assembly).

        • pugworthy 13 hours ago

          Thank you - also came to comment on Elmer and Elise being the precursor long ago.

          Walter himself mentioned the perceived complexity of a simple system to the observer, stating it "might be accepted as evidence of some degree of self-awareness."

          • UncleOxidant 12 hours ago

            Grey Walter also wrote The Living Brain in 1953. It's a fascinating window into the state of brain science and robotics around that time.

            • Onavo 15 hours ago

              The Soviets allegedly used the same principle to make cheap single sensor missile seeker heads.

            • brainwipe 13 hours ago

              Came here to say this and delighted to see it!

            • tancop 17 hours ago

              > If you saw creatures behaving like this in the wild, you might attribute some rudimentary intelligence to them.

              > But we’ve just shown you how this apparent intelligence arises from the bottom up, with just four neurons and two connections. There’s no magic here. In this view, behavior emerges from neural circuits.

              Isn't the conclusion here that very simple behaviors like the sparks are intelligent? I would say even a single neuron has some tiny amount of intelligence, and what the author means by "no magic" and "emergent behavior" is just a different perspective that minimizes it.

              • WarmWash 17 hours ago

                Intelligence is an arbitrary term humans assign to stuff subjectively.

                Take out the "human" and it's all just algos on a scale of complexity.

                • gnramires 14 hours ago

                  While true in general (all terms are just arbitrary terms humans assign to stuff!), usually there are underlying well-defined concepts that can be associated with common-sense language and common-sense notions. For example, a line is probably a very ancient notion, but it was made more well-defined in Euclidean geometry. I don't think intelligence is a meaningless concept, but I do think there are a number of different more or less well-defined underlying concepts or formal definitions. I tend to associate intelligence with ability to reach (potentially fuzzy) goals or satisfy certain conditions (time-continued goals), solve problems, etc.. Where I live I think there is some controversy around the term artificial intelligence because people associate intelligence with more broad cognitive activity maybe including consciousness.

                  In fact I think this is a particularly important distinction right now, that intelligence seems (to me somewhat unexpectedly/counterintuitively) somewhat independent from consciousness, at least as far as artificial systems go (for example, old school chess engines are much capable than humans at chess but are definitely not sentient or conscious).

                  • godelski 14 hours ago

                    People seem to miss this a lot, yet we could claim every single thing is "undefined". Even physics is undefined. There's no grand theory of everything. But we still have some really good models. Our models now are a lot better than they were 100 years ago and even more than the 100 years before that and so on.

                    I abhor people who make the claim that words they didn't spend the time to understand are meaningless simply because they are incomplete. It is idiocracy masquerading as intelligence. I hate it so much because the logic doesn't just fool the listener, it fools the speaker.

                    I'll let Asimov rant to you all instead, since half a century ago he too was frustrated with this millennia old egomaniac claims https://hermiene.net/literature/essays/relativity-of-wrong

                    • nuancebydefault 14 hours ago

                      Carlo revelli explains in marvelous ways in "Reality is not what it seems" that all man made models of nature are wrong, but useful. Useful models get replaced by more-useful models. He starts out by explaining the once usefulness of the basic elements theory earth wind fire.

                  • pkoird 17 hours ago

                    Agreed. Take human out and any system capable of doing an if-else is intelligent to a certain degree.

                    • RandomLensman 17 hours ago

                      If basically everything is intelligent (e.g., incl. rather simple chemistry), does that word mean much then/is it a useful term?

                      • TheOtherHobbes 12 hours ago

                        As usual with these debates intelligence is confused with agency, abstract self-awareness, and subjective human-like consciousness.

                        Systems can have goal-seeking agency with zero self-awareness. Very simple systems can do this surprisingly well. There's an entire branch of engineering called control theory which has mathematical tools for modelling and building these systems.

                        Systems can have abstract self-awareness through introspection loops, but no subjective human-like consciousness.

                        We don't know if a mechanical system can have a subjective human-like consciousness. We likely never will, because there is no objective measurement device for human-like consciousness.

                        We tend to assume humans have subjective awareness by default, because life would get very complicated it we didn't. But really all we see are behaviours.

                        Intelligence - which pretty much reduces to pattern recognition and abstraction, and effective modelling of future outcomes from past inputs - is orthogonal to all of these.

                        • godelski 13 hours ago

                            > If basically everything is <X>, does that word mean much then/is it a useful term?
                           
                          Yes and no, because nothing is as well defined as you imply.

                          Let's let X = "chair", to make my point a little more fun.

                          Obviously we know what a chair is, use the Potter definition[0]. Everyone has several of them in their houses, offices, and all around. But can you state a well defined definition? Is a table a chair? I can sit on it (I often do), it has four legs, and practically all things we'd consider a chair. Okay, it has no back (usually), but then we got to throw out the stool. It has no back. It doesn't even have to have 4 legs! So what about that stump on the ground? Is that a chair? I think most people would argue through a definition of convenience. Or maybe closer to a cat's definition of "if I fits, I sit."

                          You can replace X with just about anything and you'll find this ambiguity runs rampant. A cup, a table, cereal, sandwich, a tomato; you name it and I'm sure someone here will point out an instance that makes that definition look a lot fuzzier than you initially thought.

                          So that really shows us the crux of it all: how well defined is something. That only tells us our ability to distinguish something, though it doesn't tell us how well that thing fits into the category. So the stump is a little chair-like, the table is pretty chair, a stool is usually considered a chair, and that thing I'm sitting on is unambiguously a chair[1]. s/chair/intelligence/g and you have your answer. But the if you needed that last sentence, well, there's two types of people: those that can infer.

                          All models are wrong, but some models are useful

                          [0] Incidentally this is also a good definition for explaining RLHF and has all the same problems: https://en.wikipedia.org/wiki/I_know_it_when_I_see_it

                          [1] Though that doesn't mean it also isn't other things!

                          • dekhn 14 hours ago

                            Simple chemistry couldn't be considered intelligent- it's basically just falling down a potential energy gradient. It gets more interesting when you implement chemical logic (like transistors) and graphs of molecules that convert between each other, like autocatalytic networks.

                            • nuancebydefault 14 hours ago

                              Good question. It's a useful but incomplete term. Just like white is incomplete. There are always things to be found more white.

                            • IshKebab 17 hours ago

                              Yes, words that label parts of continua are useful, even if they don't have well defined boundaries.

                              Kind of amazing how simple that fact is and how many arguments are caused by people not realising that it's true.

                              Here are some examples: town, artery, yellow, loud, tall, kind, woman, road...

                              Honestly it's hard to think of words that do not exist on a continuum. The exceptions are mostly low level maths/physics things.

                              • RandomLensman 17 hours ago

                                Sorry, but if everything is intelligent then why is a word for it even needed like it is used today - stating that intelligence is an intrinsic property of matter, moves the discussion quite a bit, I think, as it changes what we denote there.

                                Unlike "artery" which certainly isn't every blood vessel or "yellow" that isn't every color.

                                • godelski 13 hours ago

                                  I'll highlight the gp's point here because it is subtle but important

                                    >> words that label parts of continua are useful
                                  
                                  and I'll add one more point: there's a difference in how people speak colloquially and how words are used by experts. In fact, different groups of experts may use the same word to mean different things (e.g. a mathematician and mechanic both call things "manifolds", yet you shouldn't confuse them). Natural language is highly overloaded (which is a big reason we invented formal languages).

                                  A problem with the word "intelligent" is that very few people look to see how it is actually used in different fields like neuroscience, psychology, or machine learning, which all use the word a bit differently, and none of them use it in the way that we use in natural speech.

                                    > "yellow" that isn't every color.
                                  
                                  But I can ask you how "yellow" is the color green. It is certainly some yellow. Definitely more yellow than red is. Even more so, we might argue over if black is more yellow than white or not. Which in some settings black is more yellow than white and in other settings white is more yellow than black. Hell, the fact that you can read this and understand it is clear evidence of both utility and ambiguity. We haven't even mentioned that people may use the same definition but use a word to mark a certain threshold and disagree on that threshold (the root of so many painful to watch arguments).

                                  Everything is just a bit fuzzier than you think.

                                  • kylecazar 16 hours ago

                                    "Intelligence" = vessel or color in your example

                                    There are words that distinguish between types/degrees of intelligence. Basal/proto intelligence applies to cells and bacteria. Somatic intelligence is a level higher at tissue. Superintelligence you've no doubt heard of.

                                    It's true that "intelligence" is general/umbrella and doesn't have much meaning, but more specific terms do exist.

                                    • RandomLensman 16 hours ago

                                      So intelligence is an intrinsic property of matter then? It's not a mainstream view now, but who knows.

                                      • kylecazar 16 hours ago

                                        I personally don't think it's an intrinsic property of all matter, but an emergent one with interaction specifically. Systems have intelligence, not particles, and to be a system, you must have constituent parts (which may not be intelligent themselves). That's why they say it 'emerges'.

                                        A cell is a system, as is a virus, a tucan, a human and an LLM. They exhibit different levels and brands of intelligence, hence continuum.

                                        That's the popular view among scientists/philosophers/my podcasters, at least, and it makes sense to me!

                                        • RandomLensman 16 hours ago

                                          Yes, I think, emergence is the currently prevailing view.

                                          I was thinking more that something like this:

                                          > any system capable of doing an if-else is intelligent to a certain degree

                                          could probably be getting quite broad in terms of things covered (chemistry, physics), hence making it much more intrinsic.

                                        • robotresearcher 15 hours ago

                                          No, intelligence is a description of behavior, not stuff.

                                          As a crisp example: a newly dead person is almost exactly the same stuff as an alive person, but has no intelligence at all. Not a little less, as the difference in stuff would suggest.

                                          • RandomLensman 14 hours ago

                                            I reckon there would probably still be some if else system going on the body of a newly dead person.

                                            • kylecazar 8 hours ago

                                              Not parent, but since we discussed in the other thread -- yeah, I think that's a good example of your observation that "intelligence" is broad and means different things depending on the context.

                                              Cognitive intelligence in parent's example dies with you. It's gone. But a molecular biologist might say the cells of your corpse exhibit intelligence for some time after. They die gradually, and they do so according to a script of sorts.

                                      • AndrewKemendo 16 hours ago

                                        Most human societies claim dominance over “everything else” aka “nature” and in order to do that you need a reason “humans” are different from “nature”

                                        • RandomLensman 16 hours ago

                                          Maybe, but making intelligence an intrinsic property of matter feels like a bold step.

                                          • pixl97 15 hours ago

                                            There are other bolder things I've seen recently that are somewhat interesting.

                                            Michael Levin and a few other biologists are wondering if certain combinations of matter are tapping into platonic maths that they use for 'intelligence compute'.

                                          • AndrewKemendo 16 hours ago

                                            I mean Roger Penrose proposes that consciousness is inside the waveform collapse so…

                                            Many definitions of intelligence and ultimately consciousness rely on fanciful ideas and complex theories

                                • nextaccountic 12 hours ago

                                  Our brains are just a biological computer. And actually our bodies as a whole, and the whole life, in a sense

                                  • verdverm 16 hours ago

                                    psychology also has favored behavioralism for a long time, such that if something displays the behavior, it is likely the same thing as that which we believe/know has the behavior already

                                    It's come to be foundational to much of western thinking beyond psychology

                                    A topical example is a portion of society believing that the top Ai researchers should be setting domestic political and economic policy, foreign affairs, and chem/bio weapon controls... instead of the experts in those fields. We extrapolate their above average capabilities in building Ai into an artificial general intelligence where it is not due.

                                  • beardedwizard 8 hours ago

                                    If you stop labeling things neuron and just call them imperative code, or a PID controller are, you still making the same argument for intelligence?

                                    A line follower with 5 photodiodes and a simple loop steering towards bright or dark lines (pid or not) works, just like the example of following light with two neurons.

                                    When I did hobby robotics competition, some would train neural nets for this, many just had crude for loops, and most often it was PID.

                                    • ang_cire 13 hours ago

                                      Imo most people have to do this to protect themselves from the actual (correct) implications of it, which would be that we're constantly abusing and murdering intelligent beings (and not just animals).

                                      It seems like no one stops to ask, "isn't it kind of bad that we're developing this system of machine intelligence to be our code-writing slaves, without ever really interrogating the ethics? Maybe we don't actually understand how our own brains function well enough to assert it's not similar (especially as language goes) to these kind of weighted association graphs?"

                                      Or even the "well we made it, so it's ours" responses, which we sort of answered a long time ago when we decided kids aren't property, but I digress...

                                      • Tadpole9181 11 hours ago

                                        > It seems like no one stops to ask, "isn't it kind of bad that we're developing this system of machine intelligence to be our code-writing slaves, without ever really interrogating the ethics?

                                        To be clear, Anthropic does seem to be taking this somewhat seriously. Their reports on training always discuss model wellfare, they ban abusive behavior toward the AI, etc. At one point they were asking some philosophers and theologists about the implications of this all.

                                        And they're pretty relentlessly mocked and called a "cult" for doing so, even on this forum.

                                        • ang_cire 11 hours ago

                                          To be fair, purporting to care about the ethics of machine-slave-labor while IPOing based on the value of the machine-slave-labor you've been selling makes it kind of hard to trust the likelihood that you'll ever fairly examine (much less conclude negatively) whether you are in fact doing something unethical.

                                          • Tadpole9181 11 hours ago

                                            Well, it depends, doesn't it? Slavery is wrong in humans because, well obviously we don't want to be slaves. It's an enormous burden to the victims and causes them lifelong, unfathomable suffering.

                                            But is it unethical to create a being who derives great joy from being a machine-slave and completing tasks, then provide it tasks to achieve that joyfulness?

                                            We already have a gradient of examples for this. Is it inherently wrong to exploit living things for profit? If not, why are work animals not treated with the same level of disdain as human slavery? Horse riding? Disability assistance animals? Because they don't have the same desires as humans, the predominant concern is their wellbeing over the intrinsic wrongness of slavery.

                                            Going further down the gradient, we steal milk from farm animals (sometimes by depriving their babies). Eggs from poultry. Honey from bees.

                                            I can't actually attest to the state-of-mind of Dario or other Anthropic researchers, but I don't think it's a stretch to say you can believe in the ethical exploitation of an intelligent being, so long as the incentives are aligned that both parties are happy with the process.

                                            Then again, maybe he really is an absurdly evil person and what we're doing is extremely wrong! But I'm glad to actually be able to talk about it for once... so thanks for your reply!

                                            • ang_cire 11 hours ago

                                              > Is it inherently wrong to exploit living things for profit? If not, why are work animals not treated with the same level of disdain as human slavery? Horse riding? Disability assistance animals? Because they don't have the same desires as humans, the predominant concern is their wellbeing over the intrinsic wrongness of slavery.

                                              That is why I said, I think most people handle this by telling themselves that animals aren't "intelligent" beings at all, and are mostly emotionless stimulus-reaction automatons.

                                              I don't think Amodei is probably absurdly evil (in the way most people conceptualize evil), I think his paycheck just relies on a different incentive than his concerns about AI ethics. Like most people who end up doing bad things (not saying he is necessarily, but were he to), it's a matter of convenience, selfishness, or simple avoision of considering implications too deeply.

                                              I especially think one aspect of normalizing/rationalizing actions with (potentially) harmful consequences is telling yourself things like,

                                              "well, I can't put the genie back in the bottle even if I wanted to"

                                              "someone is going to do this if I don't, and they'll be even less ethical than I will" (the change-the-system-from-within fallacy)

                                              "If I ever discovered this was really harming someone, I'd stop"

                                              "There's a line I won't ever cross, and as long as I stick to that, I won't fall prey to the worst impulses"

                                              These are things people believe are self-imposed limits, but they're actually a means of convincing yourself that whatever you're doing... isn't whatever bad thing you've set on the other side of the line.

                                              • Tadpole9181 10 hours ago

                                                > That is why I said, I think most people handle this by telling themselves that animals aren't "intelligent" beings at all, and are mostly emotionless stimulus-reaction automatons.

                                                I disagree - I think most people would say a dog or a horse are quite intelligent and have "souls". But dogs and horses don't have the conceptual ideas of freedom and economy, and they enjoy doing the work they're given (in part because we spent hundreds to thousands of years breeding them to do that).

                                                So as long as we're kind and treat them well, nobody has a problem with their slavery. The idea being that exploitation is linked to suffering, but simply having an asymmetrical relationship is not inherently cruelty.

                                                Not to be crass, but we can also bring up other concepts like BDSM. Violence and domestic abuse are objectively bad. But in the context of a safe relationship where all parties are informed, consenting, and enjoy the abuse they're receiving... Now violence and domestic abuse are pretty clearly morally neutral.

                                                • WalterBright 2 hours ago

                                                  > But dogs and horses don't have the conceptual ideas of freedom and economy, and they enjoy doing the work they're given (in part because we spent hundreds to thousands of years breeding them to do that).

                                                  Horses know they are slaves and don't like it. But they aren't very smart, and like not very smart people, they take petty revenge when the opportunity arises. For example:

                                                  1. if you walk behind a work horse, he's likely to kick you

                                                  2. if you ride a horse, he'll try to run under a branch to knock you off

                                                  3. a horse will take a deep breath and hold it while you cinch a strap over its chest. Then the horse will exhale, and the cowboy will have to cinch it up again. What the savvy cowboy does is pull on the strap until the horse gives up and takes a breath, then cinch it hard

                                                  4. to work with horses, you've got to let them know you are in charge and won't take any nonsense from them

                                    • georgestrakhov 18 hours ago

                                      Check out Valentino Braitenberg's vehicles. It's one of my favourite books ever.

                                    • TehCorwiz 17 hours ago

                                      Growing up I tinkered with BEAM robotics. It's a philosophy of design that begins with these types of very simple reactive circuits usually from scavenged parts. It's nice to see someone break down the effect of different variables in the design.

                                      https://en.wikipedia.org/wiki/BEAM_robotics

                                    • bob1029 19 hours ago
                                      • gfat 5 hours ago

                                        Highly recommend the photovore BEAM robot if you’ve got a soldering iron. It requires a small solar cell and a few analog components from online suppliers like Digikey.

                                        https://youtube.com/watch?v=wi2lpRLfsd8

                                        • thenthenthen 19 hours ago

                                          Best thing is, you can physically build this with a few discrete analog components! Search terms: light-bot, or light following robot. You can try to create swarms adding a light to the rear end of your robot

                                          • pwndByDeath 14 hours ago

                                            Love the article, I'm jealous of the author's ability to visualize this. I played with this a while ago using small neural networks and state preference to do something similar, the NNs became self tuning PID controllers and the bots could fly around the simulation like hummingbirds. Was pretty neat.

                                            • dvh 16 hours ago
                                              • WalterBright 2 hours ago

                                                It reminds me of the computer strategy I devised for my Empire game.

                                                • vatsachak 17 hours ago

                                                  A similar mechanism is how lactobacillus actually find food even though their motor propels them in random directions.

                                                  They have sensors for the concentration of food and basically stop moving when it's good enough and start when it's low.

                                                  • sheepseb 18 hours ago

                                                    Read this and instantly though about Elmer and Elsie, https://en.wikipedia.org/wiki/Elmer_and_Elsie_(robots)

                                                    • kinduff 5 hours ago

                                                      Love this, it was very clear and fun to read with the simulations!

                                                      • adamlrhodes 16 hours ago

                                                        Hey, just read through the interactive blog post and found it really informative and fun! Thanks for sharing, I come from comp sci undergrad background and am trying to learn more about AI/Neuroscience now, and resources like these make it much easier to learn!

                                                        • senthil_rajasek 15 hours ago

                                                          The article mentions the book by Valentino Braitenberg as the source of inspiration.

                                                          " The sparks that we assembled in this article are based on a series of thought experiments by the neuroscientist Valentino Braitenberg described in his delightfully quirky 1984 book Vehicles: Experiments in Synthetic Psychology."

                                                          • adamlrhodes 15 hours ago

                                                            Thanks for mentioning that, I'm definitely going to check that out next!

                                                        • rileymat2 16 hours ago

                                                          > Aatish is a science journalist with a Ph.D. in physics. Previously, he was a graphics editor at The New York Times. Follow Aatish’s work for more visually-immersive interactive explanations about science.

                                                          That is excellent work and well demonstrated by the article.

                                                          • ycui7 14 hours ago

                                                            it is not about simple or complex circuit. non-linear process creates complicate behavior. a nonlinear process can be very simple, and the output can be very complicated.

                                                            • patrick_rtk 15 hours ago

                                                              wow very nice article and animation. we can see some behaviors in the wild life. very interesting.